Cotton

Overview

Production: about 24.5 million tonnes (global cotton production, about 19% of all fiber produced, 2023/24 season (reported for 2024)). Main producers: China, India, Brazil, United States. [6]

Cellulose hairs growing around the seeds of the cotton plant, separated at ginning.

Feel and behavior

Absorbent and versatile; the feel depends strongly on yarn and weave.

Where you find it

T-shirts, denim, shirts, towels and bedding.

Source and geography

Cotton fiber grows as seed hairs on shrubs of the genus Gossypium. Cultivars derived from the upland species Gossypium hirsutum supply roughly 90% of world production, typically with staple lengths of about 7/8 to 1 5/16 inches. Gossypium barbadense, native to tropical South America, supplies extra-long staple (ELS) types such as American Pima, which USDA describes as about 1 1/4 to 1 9/16 inches in staple and only about 3 to 5% of the US crop. USDA outlooks track China, India, Brazil, the United States, Pakistan and Australia among the major producers.

Worth knowing

• Sea Island cotton, first planted on the South Carolina Sea Islands in 1786, fetched far higher prices than inland cotton before the boll weevil destroyed the crop in the early twentieth century.
• In 2016 Target said that sheets sold as Egyptian cotton, made by the supplier Welspun between 2014 and 2016, contained other cotton, which drew attention to DNA-based origin testing.
• The FTC has advised that multi-ply yarns count as one thread each, so a '1,000 thread count' built from plied yarns can mislead.

Types, grades and fabrics

Types and grades

Most cotton sold is Upland (Gossypium hirsutum), a medium-staple fiber used for everyday jersey, denim and towels. Gossypium barbadense supplies the extra-long-staple (ELS) types: American Pima, Egyptian Giza varieties and Sea Island. Supima is not a variety but a registered trademark that the Supima association licenses only for 100% American Pima grown in California, Arizona, Texas and New Mexico. Egyptian is a country-of-origin term: top Giza varieties such as Giza 45 are ELS, but much Egyptian cotton is ordinary long staple. Sea Island cotton was planted on the South Carolina and Georgia Sea Islands from 1786, was wiped out by the boll weevil in the early twentieth century, and survives as a small Caribbean crop. Organic cotton and Better Cotton describe farming programs, not fiber types.

Fabrics and products

Denim is a warp-faced twill with indigo-dyed warp and undyed weft; chambray gives a similar look in a lighter plain weave. Poplin is a smooth plain weave with a fine crosswise rib, and oxford is a soft basket-type weave for button-down shirts. Voile and lawn are fine, lightweight plain weaves; voile is sheerer, lawn crisper. Jersey is the single knit of T-shirts, flannel is brushed for a napped surface, and terry has uncut loops that absorb water in towels. For sheets, percale is a tight plain weave, cool and matte, while sateen floats yarns over four and under one for sheen and drape but snags and pills more readily.

Buying and care

How to judge quality

Thread count is warp plus weft yarns per square inch. The FTC has advised that each plied yarn counts as one, so an honest label reads like '300 thread count, two-ply yarn'; very high counts often come from multiplying plies. Combed, ring-spun, long-staple yarns feel smoother and pill less than carded or open-end yarns. For knits, weight matters: roughly 130 to 150 GSM feels light, around 200 GSM feels substantial. Denim is sold in ounces per square yard. Distrust cheap 'Egyptian' bedding: in 2016 Target found that sheets supplied by Welspun and labeled Egyptian cotton contained other cotton. Supima hangtags and Cotton Egypt Association seals indicate licensed, tested supply chains; 'Pima' alone is an unlicensed descriptor.

Care in detail

Most woven cotton washes well at 30 to 40 C with a regular detergent; sturdy whites, towels and sheets can go to 60 C if the label allows. Wash dark denim inside out in cool water to slow indigo loss. Expect some shrinkage in knits that were not preshrunk, so avoid a hot dryer for T-shirts; tumble on medium or line dry. Cotton takes a hot iron, up to about 200 C (three dots), best while slightly damp or with steam; press sateen on the reverse. Chlorine bleach is acceptable only on white cotton without spandex or special finishes. Rinse blood and other protein stains in cold water first, pretreat grease, and store fully dry to prevent mildew.

Care at a glance

Follow the care label and separate colors. Excess heat can shrink some cotton fabrics and weaken finishes.

Environmental and social footprint

Cotton water figures are contested because studies count different water. Chapagain and colleagues (Ecological Economics, 2006) estimated a global average virtual water content of about 3,640 cubic meters per tonne of seed cotton, rising once allocated to lint and finished cloth; the widely repeated figure of about 2,700 liters per T-shirt bundles rainfall and irrigation from field to finished shirt. An ICAC analysis put the global average at about 8,920 liters per kilogram, with about 73% supplied by rainfall and about 2,340 liters from irrigation, and roughly half of growing regions are rainfed. Irrigated cotton in dry basins is the real pressure point. Pesticide and fertilizer use, runoff and wet processing add impacts that vary by farm and mill. Forced labor in some harvests is a documented social risk.

Tradeoffs

Irrigation needs depend on place and season. Farming inputs, labor conditions and wet processing need specific evidence.

A useful question to ask: Which growing region and chain-of-custody evidence support the cotton claim?

Science

Data sheet

Cellulose-rich plant material

Seed, stem, leaf or other plant structure. Extraction and preparation vary.

Structure and chemistry

Each fiber is a single elongated plant cell. From the outside in, a mature fiber has a waxy cuticle, a thin primary wall of about 0.5 to 1 micrometer that mixes cellulose with pectins and other non-cellulosic material, a thick secondary wall that makes up roughly 90% or more of the fiber and is built from layered, spirally wound cellulose microfibrils, and a central lumen that holds the dried remains of the cell contents. Overall cellulose content is about 88 to 96.5%. When the boll opens, the tubular cell dries and collapses into a flattened, twisted ribbon. These convolutions, roughly 200 to 300 per inch, help fibers grip one another during spinning.

From source to yarn

Seed cotton is harvested by machine or by hand and taken to a gin, where saw or roller gins separate the lint from the seed. Lint is pressed into bales and classed for grade and staple length before sale. At the spinning mill, bales are opened and cleaned, then carded to individualize fibers into a sliver. Combing is an optional step that removes short fibers for finer, smoother yarns. Drawing, roving and ring, rotor or air-jet spinning follow. Woven or knitted greige fabric is then desized, scoured in alkali to remove waxes and pectins, bleached, often mercerized, and dyed or printed. The ginned seed is a separate stream for oil, meal and short linters.

Performance in use

The hydroxyl groups of cellulose bind water, so cotton absorbs readily, dries slowly and is generally at least as strong wet as dry, unlike regenerated cellulosic fibers. Its elastic recovery is low, which is why untreated cotton wrinkles. It chars and burns rather than melting. The same hydroxyl groups make it receptive to reactive, direct, vat and sulfur dyes. Mercerization, John Mercer's 1844 treatment with sodium hydroxide, swells the fiber and rounds its collapsed cross-section; Horace Lowe showed around 1889 to 1890 that holding the material under tension during treatment produces the familiar luster. Cotton is vulnerable to mildew in damp storage and to degradation by acids.

How it is identified

Burn tests are indicative only and should be done on small samples with fire precautions. Cotton ignites readily, smells like burning paper and leaves a small amount of soft gray ash with no hard bead. Under a light microscope, the flattened, twisted ribbon with convolutions and a visible lumen is characteristic; mercerized cotton looks rounder with fewer twists. FTIR confirms cellulose but does not by itself separate cotton from linen or viscose. Pima, Egyptian and organic claims cannot be confirmed by routine fiber tests and need documentary chain-of-custody evidence.

History

Timeline

1. 1793Eli Whitney applied for a patent on a mechanical cotton gin on 28 October 1793. [3]
2. 1794The cotton gin patent was granted on 14 March 1794, making short staple upland cotton far cheaper to clean of seed. [3]
3. 1844John Mercer of Lancashire treated cotton with sodium hydroxide, the process later called mercerization; his original method used no tension. [4]
4. 1889 to 1890Horace Lowe showed that holding cotton under tension during caustic treatment produces the lustrous finish now associated with mercerized cotton. [4]
5. 2016Target reported that sheets sold as Egyptian cotton and made by its supplier Welspun contained other cotton, putting origin testing in the spotlight. [5]
6. 2024Textile Exchange reported that cotton output fell about 1% to roughly 24.5 million tonnes in the 2023/24 season, about 19% of all fiber produced. [6]

Cotton has deep textile histories in Asia and the Americas. Indian cotton cloth played a major role in international trade; mechanized mills later transformed production. Its industrial history is also inseparable from plantation slavery and colonial labor systems.

The deeper record

Eli Whitney applied for a patent on a mechanical cotton gin in Philadelphia in October 1793 and received it on March 14, 1794. By cutting the labor needed to remove seeds from short-staple upland lint, from roughly a pound a day by hand to fifty pounds or more with the machine, the gin made inland upland cotton profitable. As demand rose in the early nineteenth century, cotton cultivation in the US South expanded and so did the plantation system and its demand for enslaved labor to plant and harvest the crop. US cotton exports grew from under 150,000 pounds before the gin to more than 18 million pounds by about 1800.

Labeling and law

In the United States, fiber content is disclosed by generic or common name and percentage by weight under the Textile Fiber Products Identification Act (15 U.S.C. 70 et seq.) and the FTC rules at 16 CFR Part 303. Species or origin terms such as Pima and production claims such as organic are additional representations that must be truthful and substantiated. In the EU, Regulation (EU) No 1007/2011 governs fiber names on textile labels. Organic cotton claims are commonly supported by chain-of-custody certification to standards such as GOTS or OCS; a buyer should check that a certificate covers the specific product and supplier.

This describes what rules and standards cover. It is not legal advice; jurisdiction, product form and current rule text control.

Frequently asked

Is Pima cotton the same as Supima?

Supima is a trademark licensed only for products made from 100% American-grown Pima cotton through a certified supply chain. Pima is the name for the extra-long-staple Gossypium barbadense type in general, and it can be grown in several countries, so a plain 'Pima' label carries no license or testing behind it.

Is Egyptian cotton always better?

No. Egyptian describes where the cotton was grown, and only some Giza varieties are extra long staple. Much Egyptian cotton is regular long staple, and mislabeling has been common. Look for licensed marks, such as the Cotton Egypt Association seal, and judge yarn and weave rather than the country name alone.

Does a higher thread count mean better sheets?

Not necessarily. Beyond a few hundred, counts are often inflated by counting plies separately, which the FTC considers misleading. Fiber length, combed yarns and weave matter more; a well-made 200 to 400 count percale or sateen can outlast a cheap sheet claiming 1,000.

What is the difference between percale and sateen?

Percale is a tight one-over-one-under plain weave that feels crisp, cool and matte. Sateen floats each yarn over several others, giving a smoother, warmer, shinier surface and more drape, at the cost of more snagging and pilling over time.

What does Better Cotton mean on a label?

Better Cotton is a farm-standard program. It uses mass balance, so cotton from licensed farms can be mixed with conventional cotton in mills; a Better Cotton claim supports sourcing volumes rather than guaranteeing that the fiber in a particular garment came from a licensed farm.

Sources

• Textile Exchange: Materials Market Report 2025
• Textile Exchange: Material standards
• National Cotton Council, Beltwide Cotton Conferences 2005: A review of the structure of the cotton fiber
• USDA Agricultural Handbook 566: The Classification of Cotton (archived by Texas Tech ICAC)
• USDA Economic Research Service: Cotton and Wool Outlook, December 2024
• US National Archives, Prologue: Eli Whitney's patent for the cotton gin
• ScienceDirect Topics: Gossypium barbadense
• Supima: Frequently asked questions
• Federal Trade Commission: Advisory opinion to the American Textile Manufacturers Institute on thread count
• Ecological Economics: The water footprint of cotton consumption (Chapagain et al., 2006)
• Cotton Brazil: ICAC releases cotton water footprint analysis and updates water consumption estimates
• Farm Progress: Dirty linen, a sheets scandal is roiling the cotton industry (2016)
• RSC Advances (2026): Natural fibers in sustainable materials, extraction technologies, fiber modification and performance-sustainability relationships
• US National Archives, Milestone Documents: Patent for Cotton Gin (1794)
• ScienceDirect Topics: Mercerisation, an overview

Cite this page

Chaos. (2026). Cotton. In Fibers of Earth: An independent textile atlas. https://www.hendrickresearch.com/fibers/materials/cotton/